/**
 * html2Json 改造来自: https://github.com/Jxck/html2json
 *
 *
 * author: Di (微信小程序开发工程师)
 * organization: WeAppDev(微信小程序开发论坛)(http://weappdev.com)
 *               垂直微信小程序开发交流社区
 *
 * github地址: https://github.com/icindy/wxParse
 *
 * for: 微信小程序富文本解析
 * detail : http://weappdev.com/t/wxparse-alpha0-1-html-markdown/184
 */

import wxDiscode from './wxDiscode'
import HTMLParser from './htmlparser'

function makeMap(str) {
    const obj = {}
    const items = str.split(',')
    for (let i = 0; i < items.length; i += 1) obj[items[i]] = true
    return obj
}

// Block Elements - HTML 5
const block = makeMap(
    'br,code,address,article,applet,aside,audio,blockquote,button,canvas,center,dd,del,dir,div,dl,dt,fieldset,figcaption,figure,footer,form,frameset,h1,h2,h3,h4,h5,h6,header,hgroup,hr,iframe,ins,isindex,li,map,menu,noframes,noscript,object,ol,output,p,pre,section,script,table,tbody,td,tfoot,th,thead,tr,ul,video'
)

// Inline Elements - HTML 5
const inline = makeMap(
    'a,abbr,acronym,applet,b,basefont,bdo,big,button,cite,del,dfn,em,font,i,iframe,img,input,ins,kbd,label,map,object,q,s,samp,script,select,small,span,strike,strong,sub,sup,textarea,tt,u,var'
)

// Elements that you can, intentionally, leave open
// (and which close themselves)
const closeSelf = makeMap('colgroup,dd,dt,li,options,p,td,tfoot,th,thead,tr')

function removeDOCTYPE(html) {
    const isDocument = /<body.*>([^]*)<\/body>/.test(html)
    return isDocument ? RegExp.$1 : html
}

function trimHtml(html) {
    return html
        .replace(/<!--.*?-->/gi, '')
        .replace(/\/\*.*?\*\//gi, '')
        .replace(/[ ]+</gi, '<')
        .replace(/<script[^]*<\/script>/gi, '')
        .replace(/<style[^]*<\/style>/gi, '')
}

function getScreenInfo() {
    const screen = {}
    wx.getSystemInfo({
        success: res => {
            screen.width = res.windowWidth
            screen.height = res.windowHeight
        }
    })
    return screen
}

function html2json(html, customHandler, imageProp, host) {
    // 处理字符串
    html = removeDOCTYPE(html)
    html = trimHtml(html)
    html = wxDiscode.strDiscode(html)
    // 生成node节点
    const bufArray = []
    const results = {
        nodes: [],
        imageUrls: []
    }

    const screen = getScreenInfo()
    function Node(tag) {
        this.node = 'element'
        this.tag = tag

        this.$screen = screen
    }

    HTMLParser(html, {
        start(tag, attrs, unary) {
            // node for this element
            const node = new Node(tag)

            if (bufArray.length !== 0) {
                const parent = bufArray[0]
                if (parent.nodes === undefined) {
                    parent.nodes = []
                }
            }

            if (block[tag]) {
                node.tagType = 'block'
            } else if (inline[tag]) {
                node.tagType = 'inline'
            } else if (closeSelf[tag]) {
                node.tagType = 'closeSelf'
            }

            node.attr = attrs.reduce((pre, attr) => {
                const { name } = attr
                let { value } = attr
                if (name === 'class') {
                    node.classStr = value
                }
                // has multi attibutes
                // make it array of attribute
                if (name === 'style') {
                    node.styleStr = value
                }
                if (value.match(/ /)) {
                    value = value.split(' ')
                }

                // if attr already exists
                // merge it
                if (pre[name]) {
                    if (Array.isArray(pre[name])) {
                        // already array, push to last
                        pre[name].push(value)
                    } else {
                        // single value, make it array
                        pre[name] = [pre[name], value]
                    }
                } else {
                    // not exist, put it
                    pre[name] = value
                }

                return pre
            }, {})

            // 优化样式相关属性
            if (node.classStr) {
                node.classStr += ` ${node.tag}`
            } else {
                node.classStr = node.tag
            }
            if (node.tagType === 'inline') {
                node.classStr += ' inline'
            }

            // 对img添加额外数据
            if (node.tag === 'img') {
                let imgUrl = node.attr.src
                imgUrl = wxDiscode.urlToHttpUrl(imgUrl, imageProp.domain)
                Object.assign(node.attr, imageProp, {
                    src: imgUrl || ''
                })
                if (imgUrl) {
                    results.imageUrls.push(imgUrl)
                }
            }

            // 处理a标签属性
            if (node.tag === 'a') {
                node.attr.href = node.attr.href || ''
            }

            // 处理font标签样式属性
            if (node.tag === 'font') {
                const fontSize = [
                    'x-small',
                    'small',
                    'medium',
                    'large',
                    'x-large',
                    'xx-large',
                    '-webkit-xxx-large'
                ]
                const styleAttrs = {
                    color: 'color',
                    face: 'font-family',
                    size: 'font-size'
                }
                if (!node.styleStr) node.styleStr = ''
                Object.keys(styleAttrs).forEach(key => {
                    if (node.attr[key]) {
                        const value =
                            key === 'size'
                                ? fontSize[node.attr[key] - 1]
                                : node.attr[key]
                        node.styleStr += `${styleAttrs[key]}: ${value};`
                    }
                })
            }

            // 临时记录source资源
            if (node.tag === 'source') {
                results.source = node.attr.src
            }

            if (customHandler.start) {
                customHandler.start(node, results)
            }

            if (unary) {
                // if this tag doesn't have end tag
                // like <img src="hoge.png"/>
                // add to parents
                const parent = bufArray[0] || results
                if (parent.nodes === undefined) {
                    parent.nodes = []
                }
                parent.nodes.push(node)
            } else {
                bufArray.unshift(node)
            }
        },
        end(tag) {
            // merge into parent tag
            const node = bufArray.shift()
            if (node.tag !== tag) {
                console.error('invalid state: mismatch end tag')
            }

            // 当有缓存source资源时于于video补上src资源
            if (node.tag === 'video' && results.source) {
                node.attr.src = results.source
                delete results.source
            }

            if (customHandler.end) {
                customHandler.end(node, results)
            }

            if (bufArray.length === 0) {
                results.nodes.push(node)
            } else {
                const parent = bufArray[0]
                if (!parent.nodes) {
                    parent.nodes = []
                }
                parent.nodes.push(node)
            }
        },
        chars(text) {
            if (!text.trim()) return

            const node = {
                node: 'text',
                text
            }

            if (customHandler.chars) {
                customHandler.chars(node, results)
            }

            if (bufArray.length === 0) {
                results.nodes.push(node)
            } else {
                const parent = bufArray[0]
                if (parent.nodes === undefined) {
                    parent.nodes = []
                }
                parent.nodes.push(node)
            }
        }
    })

    return results
}

export default html2json
